I've popped the lid off my '49 F1 3 speed top loader and I don't see any obvious damage to the gears. It was functioning when I bought the truck and when I drained the oil, it was free of chunky bits in it so I'm hesitant to tear it apart (I'm inclined to take the if it ain't broke attitude on this).

I'm not at all familiar with this transmission so my first question is: There appears to be about 0.150" end float on the main shaft spline end that I noticed when pulling the drive shaft. Is this expected on this transmission?

Secondly, are there any other items I should inspect on this transmission before I button it up?

Thanks for any and all guidance on this!
Ron

 

That's a lot of end-play on the mainshaft, likely means the rear main bearing is worn. That's a lot of play to be only from bearing wear tho. I wonder if a piece is missing, like the slinger behind the bearing? It's about 70 thou thick.

While it's open, you can gauge synchro condition by measuring the distance shown below ( courtesy of MacVP, vanpeltsales.com, a great source for trans parts):

 

Thanks for the quick response, Ross. You provided very helpful information. It sounds like I'm going to be getting into the transmission more than I expected.

The VanPelt site is a wealth of information but I wasn't able to locate the images that you posted. Can you please provide the link? I'd like to see what other tidbits of information there are on the site.

Ron

 

Here is what I’m seeing.



I’ve got zero clearance on the brass syncros. Would worn synchros cause this amount of movement or is something else going on?

 

Wow, that's crazy. The rear bearing retainer is still bolted up to the trans? I don't see the bolts for it sticking into the interior of the case. You should also have a fair portion of the rear bearing projecting into the inside, but I don't see any of it. Compare to pic below, which is of my side-loader trans, should not be greatly different. I wonder if the wrong rear bearing was installed by someone?

Did you drive the truck with this trans? I bet it jumped out of gear a lot? I believe the pics of synchros from Van Pelt's are from his book on rebuilding these trannies, which is well worth buying if you are going to go into the trans. Ford Top Loader Transmission Book

 

With your bearing and syncronizer wore out I’m guessing the thrust washers on the cluster gear are probably in the same shape along with the bearing on the input shaft. Good luck on the rebuild.

 

The rear bearing is recessed rather than slightly protruding.




So since I’m going to be tearing into this, what is the laundry list of things I should replace on this besides the syncros and thrust washers? I’ve done a lot of wrenching over the years but never opened up a transmission to rebuild so any guidance is appreciated. Vanpelt’s is closed until after New Year’s Day so I have a few days to pull my list together to order along with the book Ross mentioned.

thanks again for everyone’s help!.

Ron

 

The trans appears to still be in the truck? The first thing I'd do is pull it out. Then take a piece of plywood or steel and make a piece that will keep the trans from rolling around, like this:



Then I would carefully remove the rear bearing retainer (5 bolts). Hold the mainshaft inwards as you pull the retainer off. Let us know what you find!

 

Remove the rear bearing retainer and find out why you have so much end float. The output shaft is securely held on to the ball bearing by the speedometer gear and a Circlip, it’s a snug fit, there’s no way that shaft should move back and forth like that. With the amount of wear on that transmission you will have to completely disassemble it and figure out what you need. You might as well get what you need right and get everything on one order. I or someone could give you a grocery list of what you might need but it will not be accurate.

 

Surprise, surprise, surprise




looks like a shaft snap ring wasn’t where it’s supposed to be and that was causing the end float. I might as well pull it apart and refurbish it at this point.

thanks everyone for your support. Feel free to continue to forward suggestions, comments and things to look out for as I dive into this.

Ron

 

Yup, that’s what I thought was the problem. Don’t know how that ring could back off like that unless it wasn’t fully seated when last installed. Have fun.

 

I think someone was in there before and didn’t seat that snap ring in the groove. I wonder how long it’s been like that.

This is quite a learning experience. I’m putting together a pretty good list of what I need so thanks everyone for the advice to pull
it apart first. I understand now how there can’t be a generic list of stuff to replace. A discussion with Mr VanPelt will be necessary since all three of the synchro links are cracked and there is a groove worn into the synchro coupler. I’m curious what would cause that. I know I’ll need to replace the little links but not sure if the coupler can continue to be used with the groove. I’ll need his input on which thrust washers to order since it looks like theres a few options depending on the particular flavor of transmission.

I’ve already realized that putting it back together will be fun particularly with all those little roller bearings on the counter shaft cluster. I’m guessing there will be a disturbance in the Force when I get to that point.

Ron

 

The grove inside the synchro slider ring is normal , that’s where the three slider blocks / links rest when the transmission is in neutral . The blocks will need to be replaced. Have you measured the end play on the cluster gear? Some of the parts you may need will come in a small parts kit.

 

You can make the replacement of the cluster gear (with all its loose rollers) a breeze by doing some more work first. If you remove the throwout bearing fork from its shaft, and take the shaft it rides on out, then you can use a piece of 3/4" OD aluminum tubing that is sold at Home Depot or hardware stores as a dummy shaft. Just cut the tubing to the exact length of the cluster (6-3/4") and slide it inside with the rollers and spacer packed with grease, and drop the cluster into the bottom of the case. The "real" shaft can then be used to drive the dummy out the front of the case with no risk of the rollers coming out of place.

To get the fork off isn't easy, but not terrible. It is held on to its shaft with a pin that is peened on both ends. Grind off the mushroom on one side and drive the pin out by using a punch slid thru the inspection hole. (You can tell which end to grind off by looking at it, I don't remember which one it is) An extra set of hands really helps while doing this. You'll either have to reuse the pin or see if Van Pelt has any new ones. Mine was a very tight fit so I re-used it.
(edited to correct dummy shaft dimensions)

 

Your gears look pretty good which is good news as replacements can be costly.

Macs book coupled with the manual should help you along with folks on here. I would recommend getting a set of snap ring pliers and an assortment of brass punches if you don’t have those already.

JB